Static chromatic perimetric tests will be developed that determine the threshold for detection of visual targets based soley on their color properties. Target and background lights will be mutually exclusive in space and matched for photopic luminosity using subjectively determined heterochromatic flicker matches. Chromatic and achromatic static perimetry will be performed on selected groups of subjects, including normals, patients with established glaucomatous visual field defects, and patients with elevated intraocular pressure and no detectable visual field defects by current achromatic techniques. The hypothesis will be tested that visual fied defects mapped by color properties alone antedate or occur to a greater extent than those mapped as brightness defects in patients with glaucoma.